


Full Term

by yellowfellow



Category: Supernatural
Genre: Alpha Dean, Belly Kink, Childbirth, Fluff, Lawyer Dean, M/M, Mating Cycles/In Heat, Mpreg, Omega Sam, Pregnant Sam
Language: English
Status: In-Progress
Published: 2015-03-20
Updated: 2015-03-20
Packaged: 2018-03-18 18:50:34
Rating: Teen And Up Audiences
Warnings: Underage
Chapters: 1
Words: 1,150
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3580155
Author URL: https://archiveofourown.org/users/yellowfellow/pseuds/yellowfellow
Summary: <blockquote class="userstuff">
              <p>Sam goes into his first heat.</p>
            </blockquote>





	Full Term

“Sam?” Dean called out as he entered the house, back from a long day in the office. Dean is twenty-eight years old and an up and coming lawyer in Peter & Jones, just about the one firm everyone else wanted to get into.

He stays with his younger brother, Sam who is struggling to graduate from college. John, their father is travelling the world, and they are lucky to see him once a year.

“Sam?” Dean called out louder as he took off his tie and blazer, “Sam! I have got your favorite chicken steak from across the street. You better get your ass out of the room now!”

Dean was greeted by silence. It was only when he finally settled down that he smelled it. The scent started off light but as he approached Sam’s room it grew heavier, an unmistakable sweet musky smell coming out from Sam’s room.

“Damn it.” The first he thought to call was Uncle Bobby. Uncle Bobby was a Beta and will be of no threat at the moment. But he remembered that Uncle Bobby was halfway around the globe with their father.

An Omega in heat is weak and vulnerable, there is no one Dean trusts enough to ask for help.

He opens the door and his knees almost buckled. He breathed heavily, as he spotted his brother curled up in the corner of his bed, completely naked and moaning softly to himself.

“Sam?” He called out again.”

“Dean… Dean…” Sam whispered, his brows furrowed in pain, “it hurts, Dean.”

“I know… I know…” Dean instinctively reached out for his brother, despite knowing it was the wrong move.

Sam immediately grabbed him, pushing himself into Dean’s arms, “Dean…”He wanted to say more but his throat was sore like the rest of his body, his mind clouded and he could not seem to think, much less say anything.

“Fucking hurts, Dean.” He whimpers, rubbing himself against his elder brother.

“I got you, Sammy. I got you.” Dean stroked his head. At that moment Dean knew he had no choice, there was no other Alphas around. Not like Dean will ever let another Alpha get near his brother. No fucking way. John as not around. Bobby was not here. If he did not help Sam then Sam will die. He had seen an Omega died from unfulfilled heat before and it wasn’t pretty. No way will he allow Sam to go through that.

But he could not do anything, not before Sam asks. Sammy is his baby brother, 10 years younger than him. He couldn’t take Sammy, not without his permission.

He suppressed his urge as he continued to stroke Sam’s sweaty forehead, “I am here, Sammy, I’ve got you.”

He can feel the muscles cramping under Sam’s belly and he can feel his own cock hardening. 

“This is driving me insane, I…” Sam was practically trembling in Dean’s arms as he pushes his bulge against his elder brother.

“Oh God… Help me Dean. Save me.” Sam spreads his legs open, inviting Dean into him, “Help me… Dean.”

Dean needs no further instructions. He pushes Sam down onto the bed facing down, growling softly, “I am gonna take care of this for you.”

He sticks his fingers up Sam’s wet hole, the other hand unbuckling and shrugging off his pants and boxers, revealing his harden cock. He looks at Sam’s slim, lean body and oh gosh, so gorgeous, how did he managed to resist this for so many years?  
“Need you in me now!” Sam pants, slamming his own body against Dean’s, hoping to shove Dean’s cock into his hole.

“Sammy, Sammy,” Dean sucks wildly at Sam’s neck, “We have no condoms here, Sammy. If I get into you then you might, you will get pregnant.”

Sam grabs Dean closer to him, “So go on and fill me with your pups. Haven’t you been dreaming of it for years? Want… Want to be filled with your pups.”

“Fuck. Sammy. Is this your heat talking? Because there’s no way out after this.” Sam was right. For years Dean has been dreaming of fucking Sam, of filling Sam with his sperms… His pups. To watch his little brother swell up with his pups. But Sam had been too young, and Dean had to suppress his urge.

But now… But now Sam is eighteen… And already experiencing his first heat… And actually welcoming him in. Dean knows that even if Sam says no there’s no way out now, he is going in, no matter what, his Alpha instincts coming in.

“Need you in me now Dean!” Sam practically screams.

And with no further warning, Dean slams his swollen cock into the hole and Sam cries out, his hole stretched painfully. Dean showed no mercy, shoving himself deep into Sam, as he leaned down and sank his teeth into Sam’s neck, marking Sam as his. Sam growls and he starts moving, pushing himself against Dean, allowing Dean to enter deeper into him. He rocks faster and faster until both of them came, at the same time.

The toppled onto the bed, Sam safely in Dean’s arms as they of them panted breathlessly.

“You are mine now, all mine.” Dean whispers, stroking Sam’s back, “You and the pups in you, all mine.”

“All yours.” Sam nods, “Always been yours.”

\--

The next morning when Sam woke up he was all cleaned up. The sheets were changed and he was wearing a fresh set of clothes.  
Dean.

And Sam’s heart swells thinking of his brother, his Alpha, caring for him when he was asleep.

He sat up, about to look for Dean when he sensed something different. There was this warm, tickling feeling down his belly, and he knew then that he was definitely pregnant.

With him being in his first heat and Dean entering him like this without any protection, there would have been no way that he wasn’t pregnant. He places his hand on his still flat abdomen and smiles at himself. He was expecting Dean’s pups. And nothing pleases him more than that.

“Sammy?” Dean calls out gently as he enters the room. He smiles when he sees his brother awake and sitting on the bed. He went in and enveloped Sam into a hug, nuzzling his neck.

“Sammy.”

“I am pregnant, Dean.”

“I know.” Dean pressed a hand on Sam’s stomach.

“Do you know how many?” Sam asked, curious.

“It’s too early to know. You will be able to feel it soon. We are both young, and the first litter is usually the biggest, so I supposed at least three.”

“Three?” Sam repeats. The number should scare him but it did not. Instead he felt pleased with himself, that he was so fertile for his Alpha.

“Maybe more. You are so full with my pups, Sammy.” Dean leans down and kisses his mate, his heart swelling with pride.  
\--


End file.
